#include <stdio.h>
#include "add.h"
#include "sub.h"

int main()
{
    int a = 20, b = 10;

    int x = add(a, b);
    printf("%d+%d = %d\n", a, b, x);

    int y = sub(a, b);
    printf("%d-%d = %d\n", a, b, y);
    return 0;
}